2721260767657 has 2 divisors, whose sum is σ = 2721260767658. Its totient is φ = 2721260767656.

The previous prime is 2721260767607. The next prime is 2721260767723. The reversal of 2721260767657 is 7567670621272.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1707984996201 + 1013275771456 = 1306899^2 + 1006616^2 .

It is a cyclic number.

It is not a de Polignac number, because 2721260767657 - 2³⁵ = 2686901029289 is a prime.

It is not a weakly prime, because it can be changed into another prime (2721260767607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1360630383828 + 1360630383829.

It is an arithmetic number, because the mean of its divisors is an integer number (1360630383829).

Almost surely, 2^{2721260767657} is an apocalyptic number.

It is an amenable number.

2721260767657 is a deficient number, since it is larger than the sum of its proper divisors (1).

2721260767657 is an equidigital number, since it uses as much as digits as its factorization.

2721260767657 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20744640, while the sum is 58.

The spelling of 2721260767657 in words is "two trillion, seven hundred twenty-one billion, two hundred sixty million, seven hundred sixty-seven thousand, six hundred fifty-seven".